The present invention relates to lift gates, particularly for automobile vehicles and vehicles intended for handicapped persons. It relates more particularly to a device for automatically closing the elevator deck of such a lift gate, of the type constituted by a parallelogram deformable under the action of drive means, for example mechanical, electrical or hydraulic drive means.
Up to the present time, lift gate decks were generally closed manually or by means of a complex and expensive mechanism. In the prior art, U.S. Pat. No. 3,233,758 for example discloses an elevator device for rear end board of a transport vehicle, this device being constituted, like many other previously known elevator devices, by a deformable parallelogram actuated by a hydraulic jack. French Pat. No. 912303 also discloses an elevator device in which the tipping movement of the deck in horizontal position is limited by extensible connecting rods of which the adjustable minimum length serves to vary the slewability or twisting of the deck, and it will be noted that the elongation of the connecting rod serves only to allow the deck to rise and close, but it does not perform this function automatically.